It is known practice to manufacture a tire blank by winding onto a drum a strip forming very many turns. By conveniently positioning the strip during the winding, a particular shape and dimensions are given to the profile of the blank. It is known practice notably to form the larger portion of the tread of the blank by means of strips having a surface area with a relatively large section and then to define the outer shape of the blank with another type of strip having a surface area with a smaller section, and hence a reduced thickness, making it possible to give a more detailed shape to the outer face of the blank.
Each strip is manufactured by extrusion and then immediately wound so as to form the blank. Changing the type of strip therefore requires an intervention that interrupts the manufacture, for example a new adjustment of the extruder. Similarly, when it is desired to manufacture a blank for a tire of a different type requiring a strip of which the section has different characteristics, it is necessary to modify the adjustment of the extruder. These interventions slow down the manufacture of one and the same blank or of a series of blanks corresponding to different models.